DIALOG(3) BSD Library Functions Manual DIALOG(3)NAME
draw_shadow, draw_box, line_edit, strheight, strwidth, dialog_create_rc,
dialog_yesno, dialog_noyes, dialog_prgbox, dialog_msgbox, dialog_textbox,
dialog_menu, dialog_checklist, dialog_radiolist, dialog_inputbox,
dialog_clear_norefresh, dialog_clear, dialog_update, dialog_fselect,
dialog_notify, dialog_mesgbox, dialog_gauge, init_dialog, end_dialog,
use_helpfile, use_helpline, get_helpline, restore_helpline, dialog_ftree,
dialog_tree — provide a simple ncurses-based GUI interface
SYNOPSIS
#include <dialog.h>
void
draw_shadow(WINDOW *win, int y, int x, int height, int width);
void
draw_box(WINDOW *win, int y, int x, int height, int width, chtype box,
chtype border);
int
line_edit(WINDOW *dialog, int box_y, int box_x, int flen, int box_width,
chtype attr, int first, unsigned char *result, int attr_mask);
int
strheight(const char *p);
int
strwidth(const char *p);
void
dialog_create_rc(unsigned char *filename);
int
dialog_yesno(unsigned char *title, unsigned char *prompt, int height,
int width);
int
dialog_noyes(unsigned char *title, unsigned char *prompt, int height,
int width);
int
dialog_prgbox(unsigned char *title, const unsigned char *line,
int height, int width, int pause, int use_shell);
int
dialog_textbox(unsigned char *title, unsigned char *file, int height,
int width);
int
dialog_menu(unsigned char *title, unsigned char *prompt, int height,
int width, int menu_height, int cnt, void *it, unsigned char *result,
int *ch, int *sc);
int
dialog_checklist(unsigned char *title, unsigned char *prompt, int height,
int width, int list_height, int cnt, void *it,
unsigned char *result);
int
dialog_radiolist(unsigned char *title, unsigned char *prompt, int height,
int width, int list_height, int cnt, void *it,
unsigned char *result);
int
dialog_inputbox(unsigned char *title, unsigned char *prompt, int height,
int width, unsigned char *result);
char *
dialog_fselect(char *dir, char *fmask);
int
dialog_dselect(char *dir, char *fmask);
void
dialog_notify(char *msg);
int
dialog_mesgbox(unsigned char *title, unsigned char *prompt, int height,
int width);
void
dialog_gauge(char *title, char *prompt, int y, int x, int height,
int width, int perc);
void
use_helpfile(char *hfile);
void
use_helpline(char *hline);
char *
get_helpline(void);
void
dialog_clear_norefresh(void);
void
dialog_clear(void);
void
dialog_update(void);
void
init_dialog(void);
void
end_dialog(void);
int
dialog_ftree(unsigned char *filename, unsigned char FS,
unsigned char *title, unsigned char *prompt, int height, int width,
int menu_height, unsigned char **result);
int
dialog_tree(unsigned char **names, int size, unsigned char FS,
unsigned char *title, unsigned char *prompt, int height, int width,
int menu_height, unsigned char **result);
DESCRIPTION
The dialog library attempts to provide a fairly simplistic set of fixed-
presentation menus, input boxes, gauges, file requestors and other gen‐
eral purpose GUI (a bit of a stretch, since it uses ncurses) objects.
Since the library also had its roots in a shell-script writer's utility
(see the dialog(1) command), the early API was somewhat primitively based
on strings being passed in or out and parsed. This API was later
extended to take either the original arguments or arrays of
dialogMenuItem structures, giving the user much more control over the
internal behavior of each control. The dialogMenuItem structure inter‐
nals are public:
typedef struct _dmenu_item {
char *prompt;
char *title;
int (*checked)(struct _dmenu_item *self);
int (*fire)(struct _dmenu_item *self);
int (*selected)(struct _dmenu_item *self, int is_selected);
void *data;
char lbra, mark, rbra;
long aux;
} dialogMenuItem;
The prompt and title strings are pretty much self-explanatory, and the
checked and fire function pointers provide optional display and action
hooks (the data variable being available for the convenience of those
hooks) when more tightly coupled feedback between a menu object and user
code is required. The selected hook also allows you to verify whether or
not a given item is selected (the cursor is over it) for implementing
pretty much any possible context-sensitive behavior. A number of clever
tricks for simulating various kinds of item types can also be done by
adjusting the values of lbra (default: '['), mark (default: '*' for radio
menus, 'X' for check menus) and rbra (default: ']') and declaring a rea‐
sonable checked hook, which should return TRUE for the “marked” state and
FALSE for “unmarked”. The aux field is not used internally, and is
available for miscellaneous usage. If an item has a fire hook associated
with it, it will also be called whenever the item is "toggled" in some
way and should return one of the following codes:
#define DITEM_SUCCESS 0 /* Successful completion */
#define DITEM_FAILURE 1 /* Failed to "fire" */
The following flags are in the upper 16 bits of return status:
#define DITEM_LEAVE_MENU (1 << 16)
#define DITEM_REDRAW (1 << 17)
#define DITEM_RECREATE (1 << 18)
#define DITEM_RESTORE (1 << 19)
#define DITEM_CONTINUE (1 << 20)
Two special globals also exist for putting a dialog at any arbitrary X,Y
location (the early designers rather short-sightedly made no provisions
for this). If set to zero, the default centering behavior will be in
effect.
Below is a short description of the various functions:
The draw_shadow() function draws a shadow in curses window win using the
dimensions of x, y, width and height.
The draw_box() function draws a bordered box using the dimensions of x,
y, width and height. The attributes from box and border are used, if
specified, while painting the box and border regions of the object.
The line_edit() function invokes a simple line editor with an edit box of
dimensions box_x, box_y and box_width. The field length is constrained
by flen, starting at the first character specified and optionally dis‐
played with character attributes attr. The string being edited is stored
in result. Returns 0 on success, 1 on Cancel, and -1 on failure or ESC.
The strheight() function returns the height of string in p, counting new‐
lines.
The strwidth() function returns the width of string in p, counting new‐
lines.
The dialog_create_rc() function dumps dialog library settings into
filename for later retrieval as defaults. Returns 0 on success, -1 on
failure.
The dialog_yesno() function displays a text box using title and prompt
strings of dimensions height and width. Also paint a pair of Yes and No
buttons at the bottom. The default selection is Yes. If the Yes button
is chosen, return FALSE. If No, return TRUE.
The dialog_noyes() function is the same as dialog_yesno(), except the
default selection is No.
The dialog_prgbox() function displays a text box of dimensions height and
width containing the output of command line. If use_shell is TRUE, line
is passed as an argument to sh(1), otherwise it is simply passed to
exec(3). If pause is TRUE, a final confirmation requestor will be put up
when execution terminates. Returns 0 on success, -1 on failure.
The dialog_textbox() function displays a text box containing the contents
of file with dimensions of height and width.
The dialog_menu() function displays a menu of dimensions height and width
with an optional internal menu height of menu_height. The cnt and it
arguments are of particular importance since they, together, determine
which of the 2 available APIs to use. To use the older and traditional
interface, cnt should be a positive integer representing the number of
string pointer pairs to find in it (which should be of type char **), the
strings are expected to be in prompt and title order for each item and
the result parameter is expected to point to an array where the prompt
string of the item selected will be copied. To use the newer interface,
cnt should be a negative integer representing the number of
dialogMenuItem structures pointed to by it (which should be of type
dialogMenuItem *), one structure per item. In the new interface, the
result variable is used as a simple boolean (not a pointer) and should be
NULL if it only points to menu items and the default OK and Cancel but‐
tons are desired. If result is non-NULL, then it is actually expected to
point 2 locations past the start of the menu item list. it is then
expected to point to an item representing the Cancel button, from which
the prompt and fire actions are used to override the default behavior,
and it to the same for the OK button.
Using either API behavior, the ch and sc values may be passed in to pre‐
serve current item selection and scroll position values across calls.
The dialog_checklist() function displays a menu of dimensions height and
width with an optional internal menu height of list_height. The cnt and
it arguments are of particular importance since they, together, determine
which of the 2 available APIs to use. To use the older and traditional
interface, cnt should be a positive integer representing the number of
string pointer tuples to find in it (which should be of type char **),
the strings are expected to be in prompt, title and state ("on" or "off")
order for each item and the result parameter is expected to point to an
array where the prompt string of the item(s) selected will be copied. To
use the newer interface, cnt should be a negative integer representing
the number of dialogMenuItem structures pointed to by it (which should be
of type dialogMenuItem *), one structure per item. In the new interface,
the result variable is used as a simple boolean (not a pointer) and
should be NULL if it only points to menu items and the default OK and
Cancel buttons are desired. If result is non-NULL, then it is actually
expected to point 2 locations past the start of the menu item list. it
is then expected to point to an item representing the Cancel button, from
which the prompt and fire actions are used to override the default behav‐
ior, and it to the same for the OK button.
In the standard API model, the menu supports the selection of multiple
items, each of which is marked with an `X' character to denote selection.
When the OK button is selected, the prompt values for all items selected
are concatenated into the result string.
In the new API model, it is not actually necessary to preserve "check‐
list" semantics at all since practically everything about how each item
is displayed or marked as "selected" is fully configurable. You could
have a single checklist menu that actually contained a group of items
with "radio" behavior, "checklist" behavior and standard menu item behav‐
ior. The only reason to call dialog_checklist() over dialog_radiolist()
in the new API model is to inherit the base behavior, you are no longer
constrained by it.
Returns 0 on success, 1 on Cancel, and -1 on failure or ESC.
The dialog_radiolist() function displays a menu of dimensions height and
width with an optional internal menu height of list_height. The cnt and
it arguments are of particular importance since they, together, determine
which of the 2 available APIs to use. To use the older and traditional
interface, cnt should be a positive integer representing the number of
string pointer tuples to find in it (which should be of type char **),
the strings are expected to be in prompt, title and state ("on" or "off")
order for each item and the result parameter is expected to point to an
array where the prompt string of the item(s) selected will be copied. To
use the newer interface, cnt should be a negative integer representing
the number of dialogMenuItem structures pointed to by it (which should be
of type dialogMenuItem *, one structure per item. In the new interface,
the result variable is used as a simple boolean (not a pointer) and
should be NULL if it only points to menu items and the default OK and
Cancel buttons are desired. If result is non-NULL, then it is actually
expected to point 2 locations past the start of the menu item list. it
is then expected to point to an item representing the Cancel button, from
which the prompt and fire actions are used to override the default behav‐
ior, and it does the same for the traditional OK button.
In the standard API model, the menu supports the selection of only one of
multiple items, the currently active item marked with an `*' character to
denote selection. When the OK button is selected, the prompt value for
this item is copied into the result string.
In the new API model, it is not actually necessary to preserve "radio
button" semantics at all since practically everything about how each item
is displayed or marked as "selected" is fully configurable. You could
have a single radio menu that actually contained a group of items with
"checklist" behavior, "radio" behavior and standard menu item behavior.
The only reason to call dialog_radiolist() over dialog_checklistlist() in
the new API model is to inherit the base behavior.
Returns 0 on success, 1 on Cancel and -1 on failure or ESC.
The dialog_inputbox() function displays a single-line text input field in
a box displaying title and prompt of dimensions height and width. The
field entered is stored in result.
Returns 0 on success, -1 on failure or ESC.
The dialog_fselect() function brings up a file selector dialog starting
at dir and showing only those file names matching fmask.
Returns filename selected or NULL.
The dialog_dselect() function brings up a directory selector dialog
starting at dir and showing only those directory names matching fmask.
Returns directory name selected or NULL.
The dialog_notify() function brings up a generic "hey, you!" notifier
dialog containing msg.
The dialog_mesgbox() function displays a notifier dialog, but with more
control over title, prompt, width and height. This object will also wait
for user confirmation, unlike dialog_notify().
Returns 0 on success, -1 on failure.
The dialog_gauge() function displays a horizontal bar-graph style gauge.
A value of 100 for perc constitutes a full gauge, a value of 0 an empty
one.
The use_helpfile() function for any menu supporting context sensitive
help, invokes the text box object on this file whenever the F1 key is
pressed.
The use_helpline() function displays this line of helpful text below any
menu being displayed.
The get_helpline() function gets the current value of the helpful text
line.
The dialog_clear_norefresh() function clears the screen back to the dia‐
log background color, but do not refresh the contents just yet.
The dialog_clear() function clears the screen back to the dialog back‐
ground color immediately.
The dialog_update() function does any pending screen refreshes now.
The init_dialog() function initializes the dialog library (call this rou‐
tine before any other dialog API calls).
The end_dialog() function shuts down the dialog library (call this if you
need to get back to sanity).
The dialog_ftree() function shows a tree described by the data from the
file filename. The data in the file should look like find(1) output.
For the find(1) output, the field separator FS will be “/”. If height
and width are positive numbers, they set the absolute size of the whole
dialog_ftree() box. If height and width are negative numbers, the size
of the dialog_ftree() box will be calculated automatically. menu_height
sets the height of the tree subwindow inside the dialog_ftree() box and
must be set. title is shown centered on the upper border of the
dialog_ftree() box. prompt is shown inside the dialog_ftree() box above
the tree subwindow and can contain ‘\n’ to split lines. One can navigate
in the tree by pressing UP/DOWN or ‘+’/‘-’, PG_UP/PG_DOWN or ‘b’/SPACE
and HOME/END or ‘g’/‘G’. A leaf of the tree is selected by pressing TAB
or LEFT/RIGHT the OK button and pressing ENTER. filename may contain
data like find(1) output, as well as like the output of find(1) with -d
option. Some of the transient paths to the leaves of the tree may be
absent. Such data is corrected when fed from filename.
The function returns 0 and a pointer to the selected leaf (to the path to
the leaf from the root of the tree) into result, if the OK button was
selected. The memory allocated for the building of the tree is freed on
exiting dialog_ftree(). The memory for the result line should be freed
later manually, if necessary. If the Cancel button was selected, the
function returns 1. In case of exiting dialog_ftree() on ESC, the func‐
tion returns -1.
The dialog_tree() function returns the same results as dialog_ftree().
If 0 is returned, result will contain a pointer from the array names.
SEE ALSOdialog(1), ncurses(3)HISTORY
These functions appeared in FreeBSD 2.0 as the dialog(1) command and were
soon split into a separate library and command by Andrey Chernov. Marc
van Kempen implemented most of the extra controls and objects, Jordan
Hubbard added the dialogMenuItem renovations and this man page and
Anatoly A. Orehovsky implemented dialog_ftree() and dialog_tree().
AUTHORS
The primary author would appear to be Savio Lam ⟨lam836@cs.cuhk.hk⟩ with
contributions over the years by Stuart Herbert
⟨S.Herbert@sheffield.ac.uk⟩, Marc van Kempen ⟨wmbfmk@urc.tue.nl⟩, Andrey
Chernov ⟨ache@FreeBSD.org⟩, Jordan Hubbard ⟨jkh@FreeBSD.org⟩ and Anatoly
A. Orehovsky ⟨tolik@mpeks.tomsk.su⟩.
BUGS
Sure!
BSD January 1, 2000 BSD